The authors refer to their approach as an "epidermal electronic system" (EES), which is basically a fancy way of saying that the device matches the physical properties of the skin (such as stiffness), and its thickness matches that of skin features (wrinkles, creases, etc.). In fact, it adheres to skin only using van der Waals forces—the forces of attraction between atoms and molecules—so no adhesive material is required. Between the flexibility and the lack of adhesive, you wouldn’t really notice one of these attached.
One of the coolest aspects of this technology is the application method: temporary (transfer) tattoo. Yes, the ones you used as a kid, where you hold the transfer sheet with the design onto your skin then dampen it to dissolve the sheet. Here, they used water-soluble polyvinyl alcohol (PVA) sheets in the same manner. Kyle Niemeyer
If that sounds like something right out of a sci-fi novel, you would be right: Peter F. Hamilton imagined semi-permanent organic circuitry – OCTattoos – for his Commonwealth Saga series. They’re the smartphone/Siri of the future built right into your skin.